Furacão LESLIE (Atlântico 2018 #AL13)

Candy

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19 Jan 2013
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Peniche - Cabo Carvoeiro
Agora a sério, esperemos que não se verifiquem esses valores...

Isso!!! Aqui em Peniche poderá fazer estragos.
Por muito que goste desta coisa de seguir temporais, desta vez não estou a achar piadinha nenhuma. Tenho duas casas, quer passe mais por Peniche ou mais por Lisboa posso vir a ter problemas. Não me agrada nadinha.
Desta vez não vou para a rua reportar.
 

Candy

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Peniche - Cabo Carvoeiro
AVISO ESTOFEX

showforecast.cgi


DISCUSSION

...Iberian Peninsula...

Hurricane Leslie is rapidly approaching Portugal and will likely bring severe to damaging wind gusts during the night hours of Sunday

Looking at the current satellite images Leslie still looks well organized with a symmetric cloud shield and cloud top temperatures of almost -70 degree C. The central pressure is estimated to be around 971 hPa.
At the moment Leslie can be found to the south of the upper-level trough. It is forecasted that it should be taken up by the trough in the upcoming hours leading to a further acceleration of its movement to the east and also leading to a beginning transition into an extratropical system during the forecast period. However, models keep Leslie as a system with a tropical appearance for a long time when approaching the Iberian peninsula. It is also forecasted that the system should stay rather strong until it will make landfall. Although increasing shear and somewhat lower SSTs should normally weaken Leslie, the interaction with the through is probably the reason why its central pressure is forecasted to not rise significantly or even drop again during the night time.

The symmetrical appearance will probably disappear in the evening hours due to the aforementioned transition process. Models forecast the strongest pressure gradient to the south and to the west of Leslie. Together with the movement speed of Leslie, the regions of the southern flank of Leslie should see the strongest gusts but with that strong gradient west of the core, the whole coastline can be affected by severe wind gusts. Winds in 925 hPa are forecasted up to 50 m/s.

Ensemble forecasts show a significant probability of wind gusts in the excess of 30 m/s in the aforementioned area. Depending on the model damaging wind gust higher than 40 m/s are well possible. A few solutions also show more than 50 m/s. The risk of severe wind gusts can also affect parts of Western and Northwestern Spain although the storm is significantly weakening more inland.

There are still uncertainties in the exact track of Leslie and in the strength it makes landfall. ICON and ECMWF are the models that show Leslie making landfall at hurricane strength on a northerly course from Lisboa to northeastern Portugal. GFS, however, has a much weaker storm that is also moving on a more southerly track. However, models are getting more and more confident concerning a strong landfall.
The time of the landfall is expected to take place at around midnight (MESZ).

Although it is rather questionable if convections (in form of lightning) may develop we decided to issue an LVL3 area for the wind risk that comes from a convectively driven system that is only slowly transforming into a low with extratropical character.

Besides the wind risk, a locally excessive precipitation threat exists since the system brings a lot of liquid water. However, models do only give little hints for higher amounts of precipitation which is probably due to the rather fast movement of Leslie and the orography of the affected area. But amounts of 30 to 80 mm in a short time frame may lead to local flash floods.

Strong low-level shear together with low LCL would lead to an enhanced threat for tornados that may also be strong. This risk is highest to the south of Leslie where also notable CAPE values of a few hundred J/kg can be expected along a developing cold front. Also, a nice maximum of moisture convergence traveling eastward can be found in the models. This is the reason why the LVL2 area was extended to the south.

There will be an update on Leslie during the day.




Isto não me parece ser nada bom...
É a primeira vez que vejo o Estofex fazer uma previsão destas para Portugal. Pelo menos que me lembre.

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Ruipedroo

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6 Out 2010
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Braga, Merelim (60m)
AVISO ESTOFEX

showforecast.cgi


DISCUSSION

...Iberian Peninsula...

Hurricane Leslie is rapidly approaching Portugal and will likely bring severe to damaging wind gusts during the night hours of Sunday

Looking at the current satellite images Leslie still looks well organized with a symmetric cloud shield and cloud top temperatures of almost -70 degree C. The central pressure is estimated to be around 971 hPa.
At the moment Leslie can be found to the south of the upper-level trough. It is forecasted that it should be taken up by the trough in the upcoming hours leading to a further acceleration of its movement to the east and also leading to a beginning transition into an extratropical system during the forecast period. However, models keep Leslie as a system with a tropical appearance for a long time when approaching the Iberian peninsula. It is also forecasted that the system should stay rather strong until it will make landfall. Although increasing shear and somewhat lower SSTs should normally weaken Leslie, the interaction with the through is probably the reason why its central pressure is forecasted to not rise significantly or even drop again during the night time.

The symmetrical appearance will probably disappear in the evening hours due to the aforementioned transition process. Models forecast the strongest pressure gradient to the south and to the west of Leslie. Together with the movement speed of Leslie, the regions of the southern flank of Leslie should see the strongest gusts but with that strong gradient west of the core, the whole coastline can be affected by severe wind gusts. Winds in 925 hPa are forecasted up to 50 m/s.

Ensemble forecasts show a significant probability of wind gusts in the excess of 30 m/s in the aforementioned area. Depending on the model damaging wind gust higher than 40 m/s are well possible. A few solutions also show more than 50 m/s. The risk of severe wind gusts can also affect parts of Western and Northwestern Spain although the storm is significantly weakening more inland.

There are still uncertainties in the exact track of Leslie and in the strength it makes landfall. ICON and ECMWF are the models that show Leslie making landfall at hurricane strength on a northerly course from Lisboa to northeastern Portugal. GFS, however, has a much weaker storm that is also moving on a more southerly track. However, models are getting more and more confident concerning a strong landfall.
The time of the landfall is expected to take place at around midnight (MESZ).

Although it is rather questionable if convections (in form of lightning) may develop we decided to issue an LVL3 area for the wind risk that comes from a convectively driven system that is only slowly transforming into a low with extratropical character.

Besides the wind risk, a locally excessive precipitation threat exists since the system brings a lot of liquid water. However, models do only give little hints for higher amounts of precipitation which is probably due to the rather fast movement of Leslie and the orography of the affected area. But amounts of 30 to 80 mm in a short time frame may lead to local flash floods.

Strong low-level shear together with low LCL would lead to an enhanced threat for tornados that may also be strong. This risk is highest to the south of Leslie where also notable CAPE values of a few hundred J/kg can be expected along a developing cold front. Also, a nice maximum of moisture convergence traveling eastward can be found in the models. This is the reason why the LVL2 area was extended to the south.

There will be an update on Leslie during the day.




Isto não me parece ser nada bom...

Ok...nem é que ligue muito ao Estofex, mas aviso 3 em Portugal? Nunca vi isso em 15 anos pelo menos...
 

guisilva5000

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16 Set 2014
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Também estou um bocado estupefacto a acompanhar este evento, primeiro como é que a tempestade tropical ainda consegue aguentar em categoria 1 em águas pouco quentes e depois a possibilidade de landfall de um sistema tropical a sair da categoria 1 em Lisboa? Algo que provavelmente nunca aconteceu.

Já tivemos tempestades graves no Inverno com núcleos a passar por Lisboa e a deixar rajadas incríveis, mas isto é mesmo algo surreal.
 

rozzo

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11 Dez 2006
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Montijo/Lisboa
Plenamente tropical já não será, mais algo "híbrido",numa fase em que ganha contornos extra tropicais e começa a formar frentes.
Se fosse puramente tropical perderia mesmo intensidade muito mais drasticamente ao aproximar do continente.
Neste caso o timing da extra tropicalização é "perfeito" e por isso mesmo depois do enfraquecimento inicial ainda como sistema puramente tropical, o cavamento e intensificação posteriores vão dar-se mesmo à chegada a Portugal continental, daí a severidade da situação.
E claro, apesar da estrutura se começar a alterar, ainda terá um núcleo quente e muito conteúdo de água precipitável, dada a sua origem tropical, portanto poderemos mesmo em algumas zonas assistir a um evento sem precedentes para o clima da nossa região.
É de facto preocupante o "adormecimento" generalizado da população e media, tantas vezes alarmistas sem necessidade. Enfim..
Esperemos que não ocorra nenhuma tragédia por desleixo como vimos o ano passado com os incêndios, quando todos os "alarmes soavam" e pouco se ligou...

A faixa de precipitação diluviana parece relativamente estreita e apontada em particular à zona do Oeste. Já o campo de vento violento é mais amplo em particular em toda a faixa litoral claro. Zonas altas como serra de Sintra e do Montejunto deverão ter rajadas bastante incríveis.
Todo o cuidado será pouco...

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Candy

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Peniche - Cabo Carvoeiro
É de facto preocupante o "adormecimento" generalizado da população e media, tantas vezes alarmistas sem necessidade. Enfim..
Esperemos que não ocorra nenhuma tragédia por desleixo como vimos o ano passado com os incêndios, quando todos os "alarmes soavam" e pouco se ligou...

É precisamente por causa dessas "tantas vezes alarmistas sem necessidade" que a minha mãe agora diz que não vem nada para cá e não se está a ralar nadinha com isto. Não quer sequer resguardar os vasos, vou ter de ser eu. Diz que vai ter trabalho e depois não vem nada!... Tal como ela será a grande maioria da população.
É como a história do Joaozinho que dizia que vinha lá o lobo e era mentira... um dia foi verdade e ninguém acreditou.

Esperemos que amanhã os media façam uma boa divulgação da gravidade da situação, caso se justifique obviamente.